Every VELUX skylight and roof window features a data plate mounted on the frame. This data plate contains the product serial number, which tells the skylight model, glass type and date of manufacture. 

When ordering accessories for existing products or requesting product servicing, you should locate this number prior to contacting us. Doing so will help us provide you with the best service possible. 

Tip: For the FS the plate is located at the bottom left frame, VS/VSE is at the bottom left sash. For the FCM the information is stamped into the side of the exterior covers.

See the images below for additional assistance.
Product ID plate for skylight